Patent GB-1228983-A (GB)
IPC: B65H19/18
Filed: 1968-07-10
Abstract: 1,228,983. Feeding webs. MASCHINENFABRIK FR NIEPMANN & CO. 10 July 1968 [18 July, 1967], No. 32897/68. Heading B8R. In apparatus for joining a web of material 3 from a new roll 3a to the web 2 from an exhausted roll 2a, or for joining a web 2 from a new roll 2a to the web 3 from an exhausted roll 3a, joining is effected by adhesive 35 on the leading end of the new web and by the pressure of rollers 13, 14 carried by levers 11, 12, and the end of the old web is severed by a cutter blade 21 coacting with one of two notched blocks 15, 16 carried by the levers 11, 12, a support 20 for the blade 21 being adjustable through 180 degrees so that the blade co-operates with the block 15 or 16 associated with the expiring web. Each web passes over a guide roller 4, around a tensioning roller 5 carried by a pivotal arm 7, and around another guide roller 6. The running web i.e. the web 2 as shown, passes by the blade 21 and between the rollers 13, 14 to feed rollers 9, 10. The leading end of the new web 3 is positionep with the adhesive part 35 between the rollers 13, 14 and is held in this position by a finger on a pivoted member 30 engaging a notch 29a in a fixed block 29. The two levers 11, 12, which are pivoted about the shafts of the rollers 9, 10, are coupled by gear-wheels 9b, 10b, so that they can move simultaneously but in opposite directions. A spring 19 biases the levers 11, 12 towards the position in which the rollers 13, 14 are in contact and one or other of the blocks 15, 16 engages the blade 21. Normally the levers 11, 12 are held in the position shown by a pivoted member 18 engaged by a stop 11a on the lever 11. When, however, the end of the web 2 is sensed as described below, a solenoid 17 is energized and through a rod 17a moves the member 18 to free the levers 11, 12 so that the block 15 co-operates with the blade 21 to cut off the web 2 and the rollers 13, 14 cause adhesion of the two webs. The tension in the new web 3 now causes the pivoted member 30 to be released from the notch 29a. The rollers 13, 14 have coverings of foam material so as to exert pressure over an appreciable area. After joining of the webs, the blade 21 is turned through 180 degrees so as to be in position for operating in due course on the new running web. For this purpose, the knife support is connected by a chain-and-sprocket to a control shaft 25 operated by a knob at its end. The sensing devices comprise two feelers (34b, Fig. 4) mounted on each arm 7, each feeler engaging one edge of the web and being associated with electrical contacts which are in parallel. When the end of the old web passes the feelers, the contacts are closed and solenoid 17 energized to effect joining and cutting. In series with the contacts associated with the left-hand lever 7 is a microswitch 31, and a similar microswitch is provided for the right-hand lever 7. Operation of the control shaft 25 to change the blade position causes a cam 25b on the shaft to open the microswitch 31 or 32 associated with the new web so as to render the corresponding feeler switches inoperative, the other microswitch being closed so that the feeler switches associated with the running web are operative. After the old web has been cut, the movement of its tensioning arm 7 causes, through connections 8b ... 8g, a brake 8a to be applied to a disc 2b or 3b on the spindle of the web roll.